Energy Aware Media Access Algorithm at the Presence of Channel State Information Error in Wireless Sensor Networks

To support the rapid emergence of applications with a large throughput and low delay requirement in wireless sensor network, design of throughput optimal energy aware algorithms has attracted researchers from a wide area of expertise. Maximum weight scheduling (MWS) is a well-known throughput optimal link scheduling algorithm. In addition to packet queue lengths, the algorithm needs to be aware of channel state information (CSI). However, perfect knowledge of channel state conditions is a very strong assumption in practical technologies. In this paper, the impact of CSI error on the performance of MWS algorithm is studied. We propose a throughput optimal link scheduling algorithm which is robust to CSI error. To consider CSI error, we propose an idea to use the state of battery at each node in order to estimate the amount of energy consumption per successful packet transmission. This information is used to revise MWS to the proposed algorithm termed as error robust energy aware scheduling (EREAS). We show that the EREAS outperforms MWS in terms of average number of failed transmissions and average delay in environments with high error probability. The theoretical results are confirmed by simulations.